A sticky egg; the Cornu arbusthuevo

 In its fetal stage, this little creature of the reptile type is fed by the juices of the tree. The thread of slime that attaches the egg to the tree acts as an umbilical cord. Glucose and water are transported to the baby Cornu abrbusthuevo (the horned bush-egg).  It is only after the birth of the creature when it develops digestive organs.  Used to digest leaves and small insects. Fully grown the arbusthuevo is comparable in size with a large frog.